Abstract: In the batchwise preparation of vinegar with approximately from 10 to 16 g of acetic acid/100 ml of vinegar by submersed fermentation of alcohol-containing mashes, for the purpose of a substantial reduction of the long starting time of the submersed vinegar fermentations known hitherto, so as to save energy and reduce the alcohol losses which are particularly high in the starting phase, a starting mash containing acetic acid bacteria with from 4 to 4.5 g of acetic acid/100 ml of mash and from 3 to 3.5% by volume of alcohol is prepared, the temperature is allowed to rise to 28.degree. C. and is held at this level, and after the beginning of fermentation in a starting period high-percentage alcohol-containing nutrient substrate, preferably with approximately 2.5 g of acetic acid/100 ml of substrate and approximately 39% by volume of alcohol is added, and fermentation is carried out.

Abstract: A device for measuring volatile constituents of a culture medium in the fermentation industry, comprising a probe, which has a permeable membrane to exchange material for a carrier medium, and a sensor responding to the content of the substance to be measured which has permeated into the carrier medium. In order that the device may be used in industrial fermenters and in order to achieve a high degree of accuracy in measurement and reproducibility of the measured values, both the permeable membrane and the sensor are disposed in the space in which the culture medium to be tested is situated, the probe being introduced into the space containing the culture medium where appropriate by way of a lock.